This invention relates to voltage sources and particularly to circuits which provide specific voltages which are dependent on the threshold voltage of transistors used in the circuit.
Such circuits are particularly useful in the field of CMOS IC's where it is advantageous to provide specific voltages whose values are proportional to the threshold voltage V.sub.T of the transistors used therein. Such transistors may be either n- or p-channel field-effect transistors. One application is in logic circuits where threshold voltage dependent voltages are required in order to switch the transistors in the circuit so that logical decisions are made by the circuit. Another application is in sensing amplifiers in which lines connected to the inputs of the amplifier are precharged by voltages proportional to the threshold voltage in order to improve the sensitivity of the amplifier.